Heretofore, an oil pressure control device for a vehicle equipped with a first oil pump driven by a traveling driving source, a second oil pump driven by an electric motor, a first flapper valve for preventing backflow of working oil to the first oil pump side, and a second flapper valve for preventing backflow of working oil to the second oil pump side, is generally known (for instance, see Patent document 1).
By the way, in the aforementioned conventional oil pressure control device for a vehicle, when switching an oil pressure source from the first oil pump to the second oil pump due to a decrease in the flow rate of oil discharged from the first oil pump, resulting from a rotational speed decrease of the traveling driving source, the supply ratio of discharge pressure supplied from the first oil pump and the supply ratio of discharge pressure supplied from the second oil pump are adjusted by means of first and second flapper valves. However, depending on an open/closed state of each of the first and second flapper valves during switching of the oil pressure source, a temporary drop in oil pressure supplied from the oil pressure source occurs and thus the oil pressure from the oil pressure source is likely to be less than a required line pressure.
It is, therefore, in view of the previously-described drawbacks of the prior art, an object of the invention to provide an oil pressure control device for a vehicle capable of preventing an oil pressure supplied from an oil pressure source from dropping below a required line pressure when switching from an oil pressure supply by means of the first oil pump to an oil pressure supply by means of the second oil pump.